Abstract: One kind of packed columns, which were filled up with three different volume ratios of zeolite and medical stone (5 ∶5, 7 ∶3, 3 ∶7; V ∶V), were used to investigate the efficiency of zeolite and medical stone to removal the nitrogen and phosphorus in synthetic urban rainfall runoff during a 7 days period. The experiments were token twice, and the results showed that 3 ∶7 ratio of packed column could removal 78.61% and 85.28% nitrogen in the first and second phase experiment respectively, and the phosphorus removal rates reached 96.73% and 94.59%; the removal efficiency of nitrogen and phosphorus of 5 ∶5 ratio packed column were 83.18% and 97.02% in the first phase, and 80.24% and 86.16% in the second phase; while in 7 ∶3 ratio packed column, about 92.39% and 80.01% nitrogen and 51.79% and 57.28% phosphorus was removed respectively. It was concluded that in considering the whole removal efficiency and regeneration capability of zeolite and medical stone, the combination of 3 ∶7 ratio was the best choice.

Key words: medical stone, nitrogen and phosphorus, removal efficiency, zeolite, medical stone, nitrogen and phosphorus, removal efficiency